The Anon M2 Sonar Lenses are here for you to upgrade the quality of your optics. These lenses have been developed by Zeiss Optics specifically for snow sports. The Sonar lens brings you the view of the mountains in high definition allowing you to see the texture of the snow better and improves your depth perception. Anon's Magna Tech Quick Lens Change Technology uses magnets that you can swap lenses in a matter of seconds when the light changes on you.